I made the video time short because you have a short time to catch a busy person's attention in a store that you probably don't know. If you go a little over you won't get dinged but try to keep it very short with the purpose in consideration.
There isn't a link you must be signed into your account to see it. Here are pictures of what you will see: You will click on edit after your video is uploaded
Once you have clicked on edit at the top of your screen you will see audio with a musical note next to it click on on audio and to the right some songs will come up in different catagories. At the bottom there is a search area to allow you to search for more music. For anyone new to this search Youtube for videos on how to make a Youtube video, edit a Youtube video, Video Manager ect you will get more pointers.